Method and apparatus for continuously chopping, pulverizing and mixing frozen raw material such as animal meat, fish meat and beans

ABSTRACT

An apparatus and method for continuously chopping, pulverizing and mixing edible material such as animal or fish meat which involves continuously chopping square-shaped frozen blocks of the material and adding thereto sodium carbonate or sodium bicarbonate, and sodium chloride or sodium caseinate, mixing and pulverizing the resultant mixture and adding an emulsifying agent thereto to prepare an emulsion. The method is further applicable to chopping, pulverizing and mixing beans by continuously chopping square-shaped frozen blocks of coarsely ground beans and pulverizing the chopped material. The apparatus includes a chopping cylinder, a chopping rotary drum rotatably mounted and having a feed screw and a plurality of chopping knives, a feeding device for feeding the blocks of frozen raw material, and a delivery ridge portion formed in an outer peripheral surface of the chopping drum, wherein the pulverizing unit has a pulverizing cylinder and a rotatably mounted pulverizing rotary drum having pulverizing knives, a plurality of scrapper blades and feeding ridge portions.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method and apparatus for continuouslychopping and pulverizing frozen raw material for thermally-gelledprotein foods, and more particularly to those enabling proteins beingthe essential components of animal meat, fish meat and beans toeffectively perform their functions to a maximum extent.

BACKGROUND ART OF THE INVENTION

Among so-called protein foods which contain proteins as essentialcomponents thereof or are eaten to ingest proteins, the thermally-gelledprotein foods vary in quality, size and shape. In order to produce thesethermally-gelled protein foods, it is required to chop, grind and mixthe raw material.

In chopping, grinding and mixing processes of the raw material, it isrequired that the raw material is chopped as finely as possible so thatas much proteins contained as possible may be extracted from cells ofthe raw material and auxiliary materials be as uniformly as possibledispersed in the raw material to function as effectively as possible tothe extracted protein. Consequently, with proteins fuctioning to amaximum extent, the products is improved in binding properties andwater-retention properties thereof. In case that such processes are noteffectively conducted, it is not possible to obtain high-qualitythermally-gelled products. Namely, the products are poor in bindingproperties and water-retention properties to result in poor-appetite.

These chopping, grinding and mixing processes suffer from many problems.For example, muscular fiber size and tenderness of the meat varydepending on cuts, sex, age, breeds and species of the slaughteranimals. Consequently, when different kinds of meat are directlyprocessed together through meat-treating machines, it is not possible toobtain good meat products with uniform particle size. Therefore, in casethat different kinds of meat are employed as the raw material for themeat products, it is necessary that the different kinds of meat aredifferently chopped coarsely in a first stage followed by a commonsecond stage in which the coarsely chopped different kinds of meat arefurther chopped together as finely as possible. This means a pluralityof stages are required there.

In addition, in the chopping, grinding and mixing processes, the rawmaterial is subjected to an external force and there is generated africtional heat. In general, proteins are non-reversibly denatured whenheated, to become denatured proteins. Accordingly, it is necessary tosuppress the generation of heat as effectively as possible. However,this is not possible in the prior art, and, therefore, hitherto it hasnot been possible to sufficiently conduct these chopping, grinding andmixing processes. As a result, in the prior art, it is not possible forproteins to sufficiently function in manufacturing the meat products. Inmanufacturing the meat products, high-grade raw material may beeffectively employed without any problem. In contrast with this,lowgrade raw material such as sinewy meat or the like containing somecomponents which prevent thermal gellation is either impossible to beemployed in many facturing of the meat products or brings about meatproducts poor in quality, even if employed.

In the prior art, since it is not possible to sufficiently conduct thechopping, grinding and mixing processes, a considerable amount ofauxiliary raw material such as salt and the like must be added to theraw material even when the high-grade raw material is employed. However,this undesirably provides such foods as containing salt at a high levelunhealthful. The present invention dissolves at a stroke the aboveproblems involved in the chopping, grinding and mixing processes of theanimal meat, fish meat and beans and provides such method and apparatusthat evable the raw material to be chopped, ground and mixedcontinuously and in a short time to give fine particles of ideal sizewithout denaturing the proteins at all.

DISCLOSURE OF THE INVENTION

An object of the present invention resides in providing a method forcontinuously chopping, pulverizing and mixing animal meat and fish meat,by continuously following the steps of:

chopping square shaped blocks of the animal meat or fish meat frozen ata temperature of from -5 to -30 ° C.;

adding, to the resultant chopped material, 0-0.5 parts by weight ofsodium carbonate or sodium bicarbonate and 0-5 parts by weight of sodiumchloride or sodium caseinate based on 100 parts by weight of the choppedmaterial to regulate the pH thereof at a range of from 6 to 8;

mixing and pulverizing the resultant mixture to prepare a fine mixture;and

adding, to the fine mixture, an emulsifying agent at a predeterminedrate to prapare an emulsion.

In the above method, the mixture may be deaerated under reducedpressure.

Another object of the present invention resides in providing a methodfor continuously chopping, pulverizing and mixing beans by continuouslyfollowing the steps of:

forming a square-shaped block of frozen beans prepared by coarselygrinding after soaking in water and frozen at a temperature of -5 to-30° C.;

chopping the square-shaped block continuously to prepare a granularmaterial; and

pulverizing the granular material.

Further object of the present invention resides in providing anapparatus for continuously chopping, pulverizing and mixing animal meat,frozen fish meat and beans comprising:

a chopping unit constructed of;

a chopping cylinder provided with at least one feed opening for feedingthe blocks of frozen raw material and at least one delivery opening fordischarging the chopped raw material,

a chopping rotary drum rotatably mounted in the chopping cylinder andhaving both a spiral ridge portion provided on its outer peripheralsurface and forming a feed screw and plural pairs of chopping kniveseach with a substantially (Goliath crane)-shaped cutting edge orientedin a rotational direction of the chopping rotary drum, each pair ofknives being arranged in row parallel to the axis, and on the outerperipheral surface, of the chopping rotary drum, with such pair asdifferent in symmetry from each other radially oppositely disposed onthe outer peripheral surface of the chopping rotary drum, the pairs ofthe knives being equally spaced apart from each other in both ofcircumferential and longitudinal directions of the chopping rotary drum,

a feeding device provided in the feed opening for feeding the block offrozen raw material therethrough, said feeding device being providedwith a means for reciprocally moving the raw material in an axialdirection of the chopping rotary drum,

an auxiliary member provided in an inner wall of the chopping cylinderfor proventing the chopped frozen raw material from passing through aclearance between the inner wall of the chopping cylinder and an outerperipheral surface of the spiral ridge portion, and

a delivery ridge portion formed in an outer peripheral surface of thechopping rotary drum at a position corresponding to that of the deliveryopening; and

a pulverizing unit constructed of;

a pulverizing cylinder provided with an inlet opening for receiving thefrozen raw material chopped by the chopping unit and an outlet openingfor discharging the frozen raw material pulverized, and;

a pulverizing rotary drum rotatably mounted in the pulverizing cylinder,said rotary drum having a plurality of pulverizing knives arranged onrows which extend in axial direction, a plurality of scraper blades eachprovided with a scraping edge and an oblique feeding surface andarranged in such spirally shifted positions corresponding to that ofsaid inlet opening so as to define a spiral path on the peripheralsurface of the rotary drum, and feeding ridge portions formed inpositions corresponding to that of said outlet opening, each of saidpulverizing knives being formed with a sectionally triangular shapededge portion having a cutting edge on the hypotenuse thereof, saidpulverizing knives of each row being fixedly arranged parallel to eachother and slightly deviated from the rotational direction of the rotarydrum, with the cutting edges directed upward and forwardly sloped inrotational direction of the pulverizing rotary drum, such that, betweena pair of rows with the pulverizing knives each different in directionof the deviation but corresponding in its position and another pair ofsimilar rows, two rows of pulverizing knives are interposed,respectively so that axial position of each knife of one pair of rowcorresponds to that of another pair of rows and each direction of saiddeviation orients at its leading edge portion toward the raw materialinlet opening and at its trailing edge portion toward the outletopening, said scraper blades being arranged such that each obliquefeeding surface constitutes a spiral element for feeding upward, andsaid outlet opening for the pulverized being arranged on a positioncorresponding to the delivery opening of the chopping rotary drum.

In the above apparatus, the chopping cylinder may be provided with atleast one feed opening for feeding a frozen auxiliary raw material.

The raw material block feeding device in the above apparatus comprises afeed sleeve connected to the feed opening provided on the choppingcylinder for feeding the frozen raw material and extending radiallyoutward therefrom and a hopper mounted on a free end portion of the feedsleeve, and such a construction is preferred that the feed sleeve has afirst holding plate for pressing the frozen raw material block againstan upper wall of the feed sleeve lest the frozen raw material shouldmove freely; an actuator for the holding plate; second holding platesfor grasping the frozen raw material to be reciprocally moved in anaxial direction of the chopping rotary drum and second actuators for thesecond holding plates, and the hopper is provided therein with a movableguide plate whose movable-end portion is engaged with an upper-endportion of the first holding plate.

In the above apparatus, the pulverizing unit can be connected to afinishing unit comprising:

a finishing cylinder having an inlet opening for receiving thepulverized raw material from the pulverizing unit and an outlet openingfor discharging the raw material subjected to a finishing treatment, and

a finishing rotary drum rotably mounted in the finishing cylinder, saidfinishing rotary drum having a plurality of finishing knives arranged onrows which extend in axial direction, a plurality of scraper blades eacharranged in such spirally shifted positions corresponding to that ofsaid inlet opening so as to define a spiral path on the peripheralsurface of the rotary drum, and feeding ridge portions formed inpositions corresponding to that of said outlet opening, each of saidfinishing knives being formed with a sectionally triangular shaped edgeportion having a cutting edge on the hypotenuse thereof, said finishingknives of each row being fixedly arranged parallel to each other andslightly deviated from the rotational direction of the rotary drum, withthe cutting edges directed upward and forwardly sloped in rotationaldirection of the finishing rotary drum, such that, between a pair ofrows with the finishing knives each different in direction of thedeviation but corresponding in its position and another pair of similarrows, two rows of finishing knives are interposed, respectively so thataxial position of each knife of one pair of rows corresponds to that ofanother pair of rows and each direction of said deviation orients at itsleading edge portion toward the raw material inlet opening and at itstrailing edge portion toward the outlet opening.

The chopping unit may be connected to the puverizing unit, with eachcylinder and rotary drum integrally connected, so that the rotary drumsmay be driven by a single common shaft. Further, the chopping unit, thepulverizing unit and the finishing unit may be connected, with eachcylinder and rotary drum integrally connected so that the rotary drumsmay be driven by a single common shaft.

The chopping unit and the pulverizing unit or the chopping unit, thepulverizing unit and the finishing unit may be indirectly connectedthrough piping.

In the method according to the present invention, the raw material andthe apparatus need not be cooled during the processing. This is becausethere is employed a frozen raw material as the starting material andthus any temperature rise is restricted by a latent heat of fusion ofthe ice or because the required time for the processing is very short toallow the frozen raw material to be completely pulverized beforemelting.

In the method of the present invention, it is required for the frozenraw material to assume a substantially square-shaped block so that anamount of the raw material processed may be kept constant, and it isalso required that the blocks have a same size in a cycle of theprocesses.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of the apparatus of the present invention forcontinuously chopping, pulverizing and mixing the frozen raw material;

FIG. 2 is a longitudinal sectional view of the chopping unit;

FIG. 3 is a cross-sectional view of the chopping unit;

FIG. 4 is a development of the pulverizing rotary drum of thepulverizing unit; FIG. 5 is a cross-sectional view of the chopping unittaken along the line V--V of FIG. 3;

FIG. 6 is a front view of the chopping knife;

FIG. 7 is a left side view of the chopping knife;

FIG. 8 is a right side view of the chopping knife;

FIG. 9 is a plan view of the chopping knife;

FIG. 10 is a longitudinal sectional view of the pulverizing unit;

FIG. 11 is a front view of the development of the pulverizing rotarydrum of the pulverizing unit;

FIG. 12 is a plan view of the development of the pulverizing rotary drumof the pulverizing unit;

FIG. 13 is a bottom view of the development of the pulverizing rotarydrum of the pulverizing unit;

FIG. 14 is a left side view of the development of the pulverizing rotarydrum of the pulverizing unit;

FIG. 15 is a partialy sectional view illustrating the relationshipbetween the pulverizing cylinder, the pulverizing knives and the scraperblades of the pulverizing unit;

FIG. 16 is a front view of the scraper blade of the pulverizing unit;

FIG. 17 is a left side view of the scraper blade;

FIG. 18 is a right side view of the scraper blade;

FIG. 19 is a plan view of the scraper blade;

FIG. 20 is a partialy sectional view illustrating the relationshipbetween the pulverizing knives and the pulverizing cylinder;

FIG. 21 is a development of finishing rotary drum; and

FIG. 22 is a modified embodiment of the apparatus of the presentinvention, in which embodiment the chopping unit, the pulverizing unitand the finishing unit are integrally combined with each other.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Now, an apparatus of the present invention for continuously chopping,pulverizing and mixing animal meat, fish meat and beans will bedescribed in detail hereinbelow with reference to the accompanyingdrawings.

FIG. 1 is a block diagram of the apparatus of the present invention. InFIGS. 2 to 5, a chopping unit of the present invention is shown. InFIGS. 6 to 9, chopping knives employed in the chopping unit are shown.

In the drawings: the reference numeral 5 denotes a chopping cylinderwith closed opposite ends; 2, 2' a square-shaped inlet opening of thechopping cylinder 5, through which inlet openings blocks 1, 1' of afrozen raw material and an auxiliary raw material thereof arerespectively supplied to the chopping cylinder 5. The inlet openings 2and 2' are provided respectively in an upper portion of the choppingcylinder 5 so as to be spaced apart from each other in a circumferentialdirection of the chopping cylinder 5 by an angle of 90. Each of theinlet openings 2 and 2' is of the same size, viz., each substantiallyequals to 3/4 of the overall axial length of the chopping cylinder 5 andsubstantially equals to 1/6 of the overall circumferential length of thechopping cylinder 5. There may be employed only the inlet opening 2 forthe raw material. It is also possible to reduce the size of the inletopening 2' for the auxiliary raw material.

The inlet openings 2 and 2' are connected with feed sleeves 7 and 7',respectively. The feed sleeves 7, 7' extend outwardly in the radialdirection of the chopping cylinder 5, through which feed sleeves 7 and7' the frozen raw material and the auxiliary raw material are suppliedto the inlet openings 2 and 2' of the chopping cylinder 5, respectively.In addition, the feed sleeves 7 and 7' are also connected, in theirfree-end portions, with hoppers 8 and 8', respectively. Each of the feedsleeves 7, 7' has a squareshaped cross section similar in shape to theinlet opening 2, 2'.

In the interior of each of the feed sleeves 7 and 7', a holding plate 10for holding the blocks to be fed and movable guide plate 9 for smoothlyguiding the blocks to be fed are so mounted that the movable guide plate9 is interlocked with the holding plate 10. An actuator 11 for causingthe holding plate 10 to press the blocks to be fed against an innersurface of each of the feed sleeves 7, 7' is mounted on an outer surfaceof each of the feed sleeves 7, 7'. In addition, further holding plats10' and actuators 11' are also provided on both sides of the feedsleeves 7, 7' so that the blocks sandwiched thereby may be reciprocatedin the axial direction of the chopping cylindet 5.

The chopping cylinder 5 is provided with a delivery opening 3tangentally extending for discharging the chopped material therefrom ona bottom portion opposite to the inlet openings 2,2.

In the chopping cylinder 5, a chopping rotary drum 21 is rotatablymounted which is provided with a feed screw 19 on its outer peripheralsurface, spirally extending along the axis of the chopping rotary drum21. The feed screw has a substantially square-shaped cross section.

As is clearly shown in FIG. 4, the feed screw 19 is provided with aplurality of notches which are spaced apart from each other at equalangular intervals of 45°. On each of the notches is mounted a choppingknife 13 which is preferably disengaged therefrom for cleaning,replacing or grinding.

As clearly shown in FIG. 6 to 9, the chopping knife 13 consists of amain body 75, a cutting edge 17 and a base 76 for mounting on thechopping rotary drum 21. The main body 75 assumes a substantially squarecubical form and both a top surface and a right side surface extendforward to assume a wedge-like shape. The front-edge portions of the topsurface and upper front-end portions of opposite side surfaces form thecutting edge 17. Consequently, the cutting edges 17 assume asubstantially (Goliath crane)-shaped form in front view. The frontsurface of the chopping knife 13 extending over the both side edges isslightly curved rearward and inward to enable articles of the choppedraw material to smoothly swallowed and flied horizontally and downwardfrom the chopping knife 13. Any of the top surface and both sidesurfaces of the chopping knife 13 is substantially flat.

In addition, the top surface is substantially horizontal or slightlyinclined sideward and rearward.

The chopping knife 13 shown in FIGS. 6 to 9 is used in pair with anothersymmetrical chopping knife 13.

An axial length in which the chopping knife 13 is to be located issubstantially equal to that of the feed opening 2, 2', because thechopping knife 13 provided in an area beyond the feed opening 2, 2',because the chopping knife 13 provided in an area beyond the feedopening 2,2' substantially fails to do its functions.

Though, in the embodiment illustrated, there are employed eighteenpieces of the chopping knives 13, the number thereof may be of coursevaried. As shown in FIG. 4, the pair of the chopping knives 13symmetrical with each other in shape are mounted, axially spaced apartat a predetermined distance or angularly spaced apart at intervals of apredetermine angle, so that there may appear, for example, the samepairs on an axially the same location angularly spaced apart at 180°.These pairs totalling to 18 chopping knives are axially spaced apartfrom each other at intervals of a predetermined length, while spacedapart from each other at equal angular intervals of 45°. Of course, thecutting edge 17 of each of the chopping knives 13 is oriented forward ina rotational direction of the chopping rotary drum 21.

The chopping knife 13 is slightly higher than the spiral ridge 19 suchthat the cutting edge 17 is substantially brought into contact with aninner surface of the chopping cylinder 5 and accordingly, apredetermined clearance is provided between an outer peripheral surfaceof the spiral ridge 19 and the inner surface of the chopping cylinder 5.

A auxialiary member 16 is mounted on an inner wall of the choppingcylinder 5 for preventing the chopped raw material from passing throughthe clearance between the inner wall of the chopping cylinder 5 and theouter peripheral surface of the spiral ridge 19. There is substantiallyno clearance between the inner surface of the chopping cylinder 5 andthe auxiliary member 16. The auxiliary member 16 is provided with aplurality of notches 56 which permit the chopping knives 13 to passtherethrough .

A pair of delivery ridges 20 are formed on diametrically opposite sidesin an outer peripheral surface of the chopping rotary drum 21 in aposition corresponding to that of the delivery opening 3 of the choppingcylinder 5 (cf. FIGS. 3, 4). Each of the delivery ridges 20 assumes asubstantially triangular shape in section and a slant surface thereof isoriented forward in the rotating direction.

FIGS. 10 to 15 show a pulverizing unit of the present invention, andFIGS. 16 to 19 a plurality of scraper blades employed in the pulverizingunit.

In the Figs., the reference numeral 25 shows a pulverizing cylinder withclosed axial end portions. The pulverizing cylinder 25 is provided withan inlet opening 23 for receiving the chopped raw material on upperportion and an outlet opening 24 for discharging the pulverized rawmaterial on lower portion. A pulverizing rotary drum 28 is rotatablymounted in the pulverizing cylinder 25.

On an outer peripheral surface of the pulverizing rotary drum 28, thereare fixedly mounted six rows of pulverizing knives 26 which extendaxially in perallel. Each of the pulverizing knives 26 consists of acommon base and a plurality of substantially triangular cutting edges26' which are integrally formed with the common base so as to extendradially outward in a direction perpendicular to the common base. Eachof the cutting edges 26' is edged at an oblique side, and the obliqueside is oriented upward. The oblique side is high at the leading portionand low at the trailing portion.

All of the cutting edges 26' of each row of the pulverizing knivesextend parallel to each other. The cutting edges 26' are slightlydeviated from the rotational direction of the pulverizing rotary drum28.

With three adjacent rows of the pulverizing knives 26 taken as one set,the cutting edges 26' of the two among the three rows are arranged onthe same positions in the circumferential direction of the pulverizingrotary drum 28 but differ in deviation from the rotational direction toopposite sides. In the remaining one row of the pulverizing knives, eachcutting edge 26' is disposed in a position corresponding to anintermediate position between adjacent two rows of the pulverizingknives 26 and is so deviated from the rotational direction of thepulverizing rotary drum 28 that the leading edges orient toward theinlet opening 23 and the trailing edges orient toward the outlet opening24. The last row serves to feed the pulverized raw material toward theoutlet opening 24. Such two sets of three adjacent rows of thepulverizing knives are disposed at equal angular intervals in the outerperipheral surface of the pulverizing rotary drum 28.

It is preferable that the pulverizing knives are detachable as is in thecase of the chopping knives.

In the outer peripheral surface of the pulverizing rotary drum 28 areprovided six pieces of scraper blades 63 each being disposed at aposition corresponding to that of the inlet opening 23 and beingprovided with a scraping edge 61 and an oblique feeding surface 62. Thescraper blades 63 are disposed axially on the same rows as those of thepulverizing knives 26 and in a spiral manner so as to define a spiralpath as a whole.

As shown in detail in FIGS. 16 to 19, each of the scraper blades 63 issubstantially similar in construction to each of the chopping knives 13and, as in case of the chopping knives 13, is mounted with each cuttingedge oriented forward in the rotational direction.

An outermost end of the cutting edge of each of the scraper blades 63 issubstantially brought into contact with an inner surface of thepulverizing drum 28.

In FIG. 20, there are shown the relative positions of the pulverizingknives 26 of the pulverizing unit and the scraper blades 63 to thepulverizing cylinder 25, the relative positions of the scraper blades 63to each other and the relative positions of the same to the chopped rawmaterial inlet opening 23.

In a pair of positions corresponding to the pulverized material outletopening 25, a pair of such feeding ridge portions 64 are provided atdiametricaly opposite sides on the outer peripheral surface of thepulverizing rotary drum 28 that have the same construction as thedelivery ridge portions 20 of the chopping drum 21.

As shown in FIG. 1, the chopping unit and the pulverizing unit areconnected through a straight communication pipe 67 for feeding thechopped raw material at the delivery opening 3 of the chopping rotarydrum 21 and the inlet opening 23 of the pulverizing rotary drum 28. Incase where both units are connected by such pipe, it is preferable forthe pipe to be as short a possible.

An upstream end portion of the communication pipe 67 for feeding thechopped raw material, viz., the portion 68 connected to the choppedmaterial delivery opening 3 is slightly reduced in diameter. This isaimed at providing, immediately downstream of said portion through whichthe chopped raw material passes, some empty space for facilitatingauxiliary raw material to be uniformly added there and also at havingsaid portion served as a seal portion when the pulverizing unit isdepressurized.

On suitable portions downstream of the small-diameter portion of thecommunication pipe 67 for feeding the chopped raw material is provided aconnecting opening 71 connecting to a vacuum pump (not shown) fordepressurizing both the insides of the communication pipe 67 and thepulverizing cylinder 25 and an input opening 72 for supplying theauxiliary raw material.

The pulverizing unit may be connected by a connecting means to afinishing unit for finishing the pulverized raw material to meat pasteby further fining. Such connecting means may simply be a pipe as shownin FIG. 1 or the pulverizing unit and the finishing unit may integrallybe connected with each other so that they may be driven by a commonrotation shaft.

The finishing unit is constructed of a finishing cylinder 32 and thefinishing rotary drum 35 and it is substantially similar in constructionto the pulverizing unit except that it is smaller in diameter as a wholethan the pulverizing unit so that the peripheral speed of the finishingrotary drum may be lowered and that the finishing rotary drum isprovided with only one set of three rows of finishing knives which aresubstantially similar in construction and arrangement to the pulverizingknives 26 (cf. FIG. 21).

As shown in FIG. 1, the pulverizing unit and the finishing unit areconnected with the outlet opening 24 of the pulverizing cylinder 25 andan inlet opening 30 of the finishing cylinder 32 are connected through astraight communication pipe 73. In a suitable portion of said pipe isprovided an inlet opening 74 for receiving the auxiliary raw material.

In the above embodiment, the chopping unit, the pulverizing unit and thefinishing unit are separately constructed and assembled with thecommunication pipes, but these units may be integrally formed, with asingle rotation shaft serving as a common shaft. Such embodiment isshown in FIG. 22. Each of the chopping unit, the pulverizing unit andthe finishing unit of the modified embodiment is substantially similarin construction to that of the above-mentioned embodiment. In themodified embodiment of vertical type in which these units are axiallyconnected with each other, raw material is received at an inlet opening2" in the lowest portion and taken out at an outlet opening 31' on a topportion.

In this embodiment, the units are integrally formed as a singlestructure, so that it is not necessary for the raw material inletopenings and the processed material outlet openings to be separatelymounted, and with the spaces between the cylinders and the rotary drumscommunicated with each other, the raw material is sent upward to besequentially processed by the three units and taken out from the productoutlet opening as a meat paste.

The finishing unit portion is constructed relatively small in diameterso that the peripheral speed may be lowered, and accordingly, theconnecting portion between the pulverizing unit and the finishing unitis made frustroconical and on the outer peripheral surface of the rotarydrum in the frustroconical portion are axially provided two rows ofvanes 81 for moving the raw material upward.

In this embodiment, the reference numeral 82 indicates a first auxiliarymaterial inlet opening, 83 a vent through which depressurization of theunit is effected and 84 a second auxiliary raw material inlet opening.

Now, operation of the continuous chopping, pulverizing and mixing by theapparatus shown in FIG. 1 will be described hereinbelow.

The frozen raw material 1 assuming a square-shaped block enters the feedsleeve 7. Since the feed sleeve 7 is inclined, the frozen raw materialblock 1 is graviated to the chopping rotary drum 21 to abut thereon.With the actuator 11 operated, the frozen block is pressed against theupper wall of the feed sleeve so as to be firmly held therein.

With the chopping rotary drum 21 rotated in this state, the block isscraped and chopped by the chopping knives 13 of the chopping rotarydrum 21 such that plural square shaped portions are formed correspondingto (Goliath crane)-shaped cutting edges of the knives 13. Accordingly,the amount per unit time of the raw material block scraped and choppedby the chopping knives 13 is always constant.

Since the chopping knives 13 are driven respectively on givencircumferences, if the raw material block is simply fed, only such givenportions are squarely scraped and chopped as above and other remainingportions are left unscraped and unchopped. This means that furtherchopping operations do not proceed. Therefore, the fed raw materialblock is reciprocally moved by the actuator 11' in the axial directionof the chopping rotary drum 21 at a specified speed. Thereby, the rawmaterial block is sequentially chopped by a given thickness. When theraw material block is chopped by the given thickness, it is gravitatedto commence the next chopping operation by the given thickness. As theraw material block is chopped, next block is supplied one after another.So long as the raw material block is supplied like this, the choppingproceeds at a specified amount per unit time.

Similarly, through another feed sleeve 7', a frozen auxiliary rawmaterial such as egg white is fed to be chopped at a constant rate inthe same manner as that of the frozen raw material block and uniformlymixed therewith. The auxiliary raw material is also chopped at aspecified amount per unit time and mixed with the raw material, andaccordingly there can be realized a uniform mixing.

The frozen raw materials are chopped into pieces of about 600 μm inparticle size by the chopping unit. In such chopping, a number of icepieces dispersed in these raw materials and broken through cuttingimpact by the chopping knives 13 serve respectively as a knife forfurther chopping the chopped raw material into small particle size.

Further, parallel since there are arranged the parallel chopping knives13, the chopped raw materials are evenly distributed and suitablydispersed thereby to be sent by the delivery ridge portion 19.

This chopping operation is carried out using such raw material as frozenat a temperature of from -5 to -30° C., and containing uniformlydispersed ice. As a result, the chopping operation does not generate anyheat, and, thus without any fear that denaturation of proteins occurs,there can be effected sufficient chopping which permits additives toreact upon proteins.

The raw materials thus chopped is fed through the delivery opening 3 ina form of a porous bar to the communication pipe 67 by means of thechoppings knives 13 which also serve to feed the chopped pieces and theridge portion 19 of the chopping rotary drum 21. Since the communicationpipe 67 is depressurized, gas in the raw material is extracted therebyand the raw material also insulated from outside air is restrained frombeing oxidized.

With the small diametered end of the communication pipe 67 provided invicinity of the delivery opening 3, an empty space appears above thechopped raw material in the communication pipe 67 in a portiondownstream thereof. Accordingly, specified amount of additives such ascoagulating agents and the like are supplied from above to the choppedraw materials to flow there together in preparation for the continuousmixing at a given rate in the following pulverizing operation.

Entering the pulverizing unit through the inlet opening 23, the solidbar-shaped chopped raw material is pulverized and successively drivenupward in dispersed condition by the scraper blades 63 into a spacedefined between the pulverizing rotary drum 28 and the pulverizingcylinder 25. The raw material of dispersed condition is pulverized insuch dispersed and floating condition in the depressurized pulverizingcylinder 25 by the cutting edges of the pulverizing knives 26 and, atthe same time is driven upward, with the coagulating agent dispersed andmixed, by the cutting edges which are arranged in an inclinationrelative to the rotational direction of the pulverizing knives. As thistime, since the raw material is still in iced contion, the pulverizedraw material pieces do not stick to each other to be coagulated keepingthe dispersed and floating condition and are spattered by thepulverizing knives 26 which are arranged in an inclination relative tothe rotational direction thereof. Thus, the pulverized raw materialpieces are not moved simply linearly but three-dimentionally to be fullypulverized into particle size of 10 m or less. As a result, there can beeffected full mixing with the additives. Further, since the pulverizingoperation of the raw material is carried out in an iced condition, therecan not be generated any heat which otherwise causes denaturation ofproteins.

After completion of pulverizing process, the pulverized raw material isdischarged from the outlet opening 24 to the finishing unit to enterthrough the communication pipe 73. The auxiliary raw material is added ,if required, midway on the communication pipe 73. In the finishing unitsubstantially similar in costruction to the pulverizing unit, the rawmaterial is further fround, mixed and finished slowly by the finishingknives which rotate at a slower speed than that of the pulverizing unitto give a meat paste which is discharged from the outlet opening 31'.

The temperature of the meat paste thus discharged from the finishingunit is substantially 0° C.

In the present invention, since the processing with employment of thefrozen raw material is accomplished in a period of time the rawmaterials still remains icy, there is no fear of heat generation thatotherwise causes denaturation of proteins to allow proteins to performtheir functions to a maximum extent, with the raw material very finelypulverized.

As a result, not only there can be provided such raw material forproducing the thermally-gelled protein foods that are superior in tasteto those processed by the conventional art with employment of the samestarting material but also there can be employed as a starting materialsuch raw material e.g. shark meat, sinewy meat and the like that havenot been employed heretofore to prepare a thermally-gelled protein foodswith the same quality as those from the common raw material. As for fishmeat, it is possible for the yield thereof be improved. In addition,such fish meat that could not been employed hitherto can now be employedas the raw material for the thermally-gelled portion foods.

Now, examples of preparation will be described below:

EXAMPLE 1 Preparation of Ground Animal Paste

Beef shank was pressed into a freezer pan and frozen therein at atemperature of -25° C. to prepare five blocks each having a size of 340mm×570 mm×120 mm and a weight of 24 Kg. The pH of the blocks was 5.54.

These blocks were chopped in the chopping unit at a rate of 887 Kg/hour.The particle size of the chopped raw material was from 0.1 to 1.0 mm.

As the same time, 9 kg of egg white blocks frozen at a temperature of-25° C. were fed through another inlet opening of the chopping unit andchopped therein as above at a rate of 67 Kg/hour to into particle sizeof from 0.1 to 1.0 mm.

The chopped meat and egg white were uniformly mixed and was dischargedfrom the chopping unit to the pulverizing unit through the communicationpipe. The temperature of the raw material when discharged from thechopping unit was -15° C. Insides of the communication pipe and thepulverizing unit were maintained at from -10 to -60 cmHg, with outsideair cut off and using a vacuum pump. Midway on the communication pipe, a0.4 Kg of sodium carbonate and a 1.4 Kg of purified sodium chloride weremixed to the chopped material respectively at rate of 3 Kg/hour and 10Kg/hour.

The chopped raw material was further pulverized by the pulverizing unitat a rate of 967 Kg/hour. The pulverized raw material remained icy andthe particle size thereof was about 5 μm in central value. Thetemperature of the pulverized raw material was -5° C. when dischargedfrom the pulverizing unit.

Then, with a 4.5 Kg of fluid egg yolk having a temperature of 5° C.continuously added midway at a rate of 33 Kg/hour by means of a fixeddelivery pump and with outside air cut off, the pulverized raw materialwas fed to the finishing unit and finished therein at a rate of 1000Kg/hour to give a bround paste having a pH of 6.60.

Sausage-like product made of the ground paste had a fixed red color evenwithout employing any colorant and was good in water retentionproperties, resilient properties and taste.

EXAMPLE 2 Preparation of Sardine Ground Paste

Sardine mead was treated in the same manner as of Example 1, with thehead, tail, internal organs and shin removed, to give five frozen blockseach having a size of 340 mm×570 mm×120 mm and a weight of 22 Kg. The pHof the blocks was 5.90.

These blocks were chopped by the chopping unit at a rate of 900 Kg/hour.The chopped sardine became particles having a particle size of from 0.1to 1.0 mm.

At the same time, blocks of egg white frozen at a temperature of -25° C.and weighing 6 Kg were fed to and chopped in the same chopping unit at arate of 50 Kg/hour to particles having the same particle size of from0.1 to 1.0 mm.

The chopped and substantially uniformly mixed sardine and egg white weredischarged from the chopping unit to the pulverizing unit through thecommunication pipe. The temperature of the raw material was -15° C. whendischarged from the chopping unit. Both insides of the communicationpipe and the pulverizing unit were maintained from -10 to -60 cm Hgusing a vacuum pump and with outside air cut off. Midway on thecommunication pipe, a 0.4 Kg of sodium carbonate and a 2.1 Kg ofpurified sodium chloride were mixed to the chopped material respectivelyat a rate of 3 Kg/hour and 17 Kg/hour. The chopped raw material waspulverized by the pulverizing unit at a rate of 970 Kg/hour. Thepulverized raw material remained icy and the particle size thereof wasabout 5 μm in central value. The temperature of the raw material was -5°C. when discharged from the pulverizing unit.

Then, with a 3.7 Kg of fluid egg yolk having a temperature of 5° C.continuously added at a rate of 30 Kg/hour by means of a fixed deliverypump and with outside air cut off, the pulverized raw material was fedto the finishing unit and finished therein at a rate of 1000 Kg/hour togive a sardine ground paste having a pH of 7.11.

Fish paste product made of the sardine ground paste was not of dumplinglike texture but of a boiled fish paste that has such a texture andtaste as those of conventional boiled fish paste. Because this productcontained emulsified sardine oil, it was quite delicious, free from thesmell of sardine.

EXAMPLE 3 Preparation of Soybean Ground Paste

Employing soybeans soaked in water to have a water content of 60.4% byweight, five frozen blocks each having a size of 340 mm×570 mm×120 mmand a weight of 26 Kg were prepared in the same manner as in Example 1.The pH of the blocks was 6.38.

These blocks were chopped by the chopping unit at a rate of 1000Kg/hour. The particle size of the chopped raw material soybeans was from0.1 to 1.0 mm. The temperature of the chopped raw material was -10° C.when discharged from the chopping unit.

The chopped soybeans were fed through the communication pipe to thepulverizing unit to be pulverized therein. Both the communication pipeand the pulverizing unit were depressurized to -10 to -60 cmHg using avacuum pump and with outside air cut off. The pulverized raw materialwas of a particle form having a particle size of about 5 μm in centralvalue and remained icy. The temperature of the ground paste was -5° C.when finished processing and the pH thereof was 6.07.

Tofu (Japanese traditional bean curd) made of the ground paste left abean-curd refuse called "Okara" in amount of 1/2 compared to that in theconventional method.

EXAMPLE 4 Preparation of Euphausia Superba Ground Paste

Employing Euphausia superba having a salt content of 1.35% by weight,five blocks each having a size of 330 mm×590 mm×75 mm and a weight of13.6 Kg were prepared in the same manner as in Example 1. The pH of theblocks was 7.10.

These blocks were chopped by the chopping unit at a rate of 1000 Kg/hourto particles having a particle size of from 0.1 to 1.0 mm. Thetemperature of the mixture was 15° C. when discharged from the choppingunit.

The chopped Euphausia superba was fed to the pulverizing unit throughthe communication pipe and pulverized therein. Insides of thecommunication pipe and the pulverizing unit were maintained from -10 to-60 cmHg using a vacuum pump and with outside air cut off. The Euphausiasuperba after pulverized still remained icy and had a particle size ofabout 5 μm in central value and the pH thereof was 6.91.

Examination of resulted ground paste of the euphausia superba revealedthe protein composition as shown in the following table. This tableshows a considerable increase of activated proteins. The grond paste ofthe euphausia superba can be used as a filler for the raw material ofthermally-gelled protein foods.

                  TABLE                                                           ______________________________________                                        Type of     Raw material Ground Paste of                                      protein     euphausia superba                                                                          euphausia                                            ______________________________________                                        water-soluble                                                                             4.1 (wt. %)  9.3 (wt. %)                                          salting-in  0.7          3.6                                                  insoluble   6.2          2.5                                                  ______________________________________                                    

I claim:
 1. A method for continuously chopping, pulverizing and mixing raw material comprising animal or fish meat, the method comprising the steps of:continuously chopping, in a fixed amount, square-shaped blocks of raw material frozen at a temperature of from -5 to -30° C.; adding, to the chopped raw material, 0-0.5 parts by weight of sodium carbonate or sodium bicarbonate and 0-5 parts by weight of sodium chloride or sodium caseinate based on 100 parts by weight of the chopped raw material to adjust the pH of the chopped material to a range of from 6 to 8; mixing and pulverizing the pH adjusted chopped material; and adding, to the pulverized material, an emulsifying agent at a predetermined rate and emulsifying the mixture by further mixing.
 2. A method for continuously chopping, pulverizing and mixing the raw material as set forth in claim 1, wherein:the chopped material is deaerated under reduced pressure after chopping.
 3. A method for continuously chopping, pulverizing and mixing beans, comprising the steps of:coarsely grinding soybeans soaked in water and forming a square-shaped block frozen at a temperature of 5 to -30° C.; chopping the block continuously into particles having a first particle size; and pulverizing the chopped material into particles having a second particle size substantially smaller than said first particle size.
 4. An apparatus for continuously chopping, pulverizing and mixing animal meat, frozen fish meat and beans comprising:a chopping unit constructed of;a chopping cylinder (5) provided with at least one feed opening (2) for feeding the blocks of frozen raw material and at least one delivery opening (3) for discharging the chopped raw material, a chopping rotary drum (21) rotatably mounted in the chopping cylinder (5) and having both a spiral ridge portion (19) provided on its outer peripheral surface and forming a feed screw and plural pairs of chopping knives (13) each with a cutting edge oriented in a rotational direction of the chopping rotary drum, each pair of knives being arranged in a row parallel to the axis, and on the outer peripheral surface, of the chopping rotary drum, wherein each pair different in symmetry from each other are radially oppositely disposed on the outer peripheral surface of the chopping rotary drum, the pairs of the knives being equally spaced apart from each other in both circumferential and longitudinal directions of the chopping rotary drum, a feeding device (7, 8) provided in the feed opening (2) for feeding the block of frozen raw material therethrough, said feeding device being provided with means for reciprocally moving the raw material in an axial direction of the chopping rotary drum (21), an auxiliary member (16) provided in an inner wall of the chopping cylinder (5) for preventing the chopped frozen raw material from passing through a clearance between the inner wall of the chopping cylinder (5) and an outer peripheral surface of the spiral ridge portion (19), and a delivery ridge portion (20) formed in an outer peripheral surface of the chopping rotary drum (21) at a position corresponding to that of the delivery opening (3); and a pulverizing unit constructed of;a pulverizing cylinder (25) provided with an inlet opening (23) for receiving the frozen raw material chopped by the chopping unit and an outlet opening (24) for discharging pulverized frozen raw material, and; a pulverizing rotary drum (28) rotatably mounted in the pulverising cylinder (25), said rotary drum having a plurality of pulverizing knives (26) arranged on rows which extend in an axial direction, a plurality of scraper blades (61) each provided with a scraping edge and an oblique feeding surface (62) and arranged in spirally shifted positions corresponding to said inlet opening (23) so as to define a spiral path on the peripheral surface of the rotary drum, and feeding ridge portions (64) formed in positions corresponding to that of said outlet opening (24), each of said pulverizing knives (26) being formed with a sectionally triangular shaped edge portion having a cutting edge (26') on a hypotenuse thereof, said pulverizing knives of each row being fixedly arranged parallel to each other and slightly deviated from the rotational direction of the rotary drum, with the cutting edges directed upward and forwardly sloped in a rotational direction of the pulverizing rotary drum, such that, between a pair of rows wherein the pulverizing knives are each different in a direction of deviation but corresponding in position and another pair of similar rows, two rows of pulverizing knives are interposed, respectively so that an axial position of each knife of one pair of rows corresponds to that of another pair of rows and each direction of said deviation is oriented at its leading edge portion toward the raw material inlet opening (23) and at its trailing edge portion toward the outlet opening (24), said scraper blades (61) being arranged such that each oblique feeding surface (62) constitutes a spiral element for feeding upward, and said outlet opening (24) for the pulverized being arranged on a position corresponding to the delivery opening (3) of the chopping rotary drum (21).
 5. An apparatus for continuously chopping, pulverizing and mixing according to claim 4 wherein said chopping cylinder (5) is provided with at least one feed opening for feeding a frozen auxiliary raw material.
 6. An apparatus for continuously chopping, pulverizing and mixing according to claim 4 wherein said raw material block feeding device(7, 8) comprises a feed sleeve(7) connected to the feed opening (2) provided on the chopping cylinder(5) for feeding the frozen raw material and extending radially outward therefrom and a hopper(8) mounted on a free end portion of the feed sleeve(7), wherein the feed sleeve(7) has a first holding plate(10) for pressing the frozen raw material block against an upper wall of the feed sleeve; an actuator(11) for the holding plate(10); second holding plates(10') for grasping the frozen raw material to be reciprocally moved in an axial direction of the chopping rotary drum(21) and second actuators(11') for the second holding plates(10'), and the hopper is provided therein with a movable guide plate(9) whose movable-end portion is engaged with an upper-end portion of the first holding plate.
 7. An apparatus for continuously chopping, pulverizing and mixing according to claim 4 wherein said pulverizing unit is connected to a finishing unit comprising;a finishing cylinder(32) having an inlet opening(30) for receiving the pulverized raw material from the pulverizing unit and an outlet opening (31) for discharging the raw material subjected to a finishing treatment, and a finishing rotary drum(35) rotably mounted in the finishing cylinder(32), said finishing rotary drum having a plurality of finishing knives(33) arranged on rows which extend in an axial direction, a plurality of scraper blades(63') each arranged in spirally shifted positions corresponding to said inlet opening so as to define a spiral path on the peripheral surface of the rotary drum, and feeding ridge portions (64') formed in positions corresponding to that of said outlet opening(31), each of said finishing knives(33) being formed with a sectionally triangular shaped edge portion(33') having a cutting edge on a hypotenuse thereof, said finishing knives(33) of each row being fixedly arranged parallel to each other and slightly deviated from the rotational direction of the rotary drum, with the cutting edges directed upward and forwardly sloped in a rotational direction of the finishing rotary drum, such that, between a pair of rows wherein the finishing knives are each different in direction of deviation but corresponding in position and another pair of similar rows, two rows of finishing knives are interposed, respectively so that an axial position of each knife of one pair of rows corresponds to that of another pair of rows and each direction of said deviation is oriented at its leading edge portion toward the raw material inlet opening(30) and at its trailing edge portion toward the outlet opening(31).
 8. An apparatus for continuously chopping, pulverizing and mixing according to claim 4 wherein said chopping unit and pulverizing unit are integrally connected, with each cylinder and rotary drum integrally connected, wherein each rotary drum is rotated by a single common rotation shaft.
 9. An apparatus for continuously chopping, pulverizing and mixing according to claim 7 wherein said chopping unit, pulverizing unit and finishing unit are connected with each cylinder and rotary drum integrally connected wherein each rotary drum is driven by a single common shaft.
 10. An apparatus for continuously chopping, pulverizing and mixing according to claim 4 wherein said chopping unit and pulverizing unit are connected through a communication pipe.
 11. An apparatus for continuously chopping, pulverizing and mixing according to claim 7 wherein said chopping unit, the pulverizing unit and the finishing unit are connected through communication pipes in order. 